I use the same rain gear for biking as i do for hiking. That is an LL Bean Goretex Rain Jacket and Pants. The good news is it keeps all the rain out. The bad news, i'm not dry hiking or biking. I too opt for warm.

In summer showers with temps above 85 degrees i will opt for no rain gear or just a water resistant biking shell. Though temps will drop into the seventies with the rain, as soon as the sun pops back out I'm warm and dry.

Still ,even though the Goretex leaves me clamy it does keep out the cold rain. In sustained rain that's a big plus. The underlayers near your skin, even if wet from sweat can trap that warm moisture near the skin and give you a wetsuit type effect. The difference being that once you stop producing heat, say at a lunch stop, things get colder quickly. But as long as you are moving, it's all good.